1. Field of the Invention
This invention relates to methods and apparatus for providing security for personnel freely moving about within a predetermined area.
2. Description of the Prior Art
With increasing levels of crime and violence in society, the problem of providing safety and security for persons freely moving about within a predetermined area has become more and more acute. Universities, hotels, industrial plants and the like have an overriding interest in providing a safe environment and a feeling of high personal safety for persons within the predetermined area defined by the university campus, hotel premises, industrial plant setting and the like.
Heretofore, persons for which a given institution, such as a university, hotel or industrial plant, desired to assure personal safety have been provided with "beeper" devices to emit alarm tones upon actuation by a person carrying such a beeper device. In such systems, the individual actuating the beeper device, to inform others that the person is in apprehension respecting his or her personal safety, depends on the goodwill and cooperation of others (who are in the local area and hear the audible "beeper" alarm) to assist the individual actuating the beeper.
Other approaches have included television monitoring cameras and the like distributed about the predetermined area. In such systems video signals are transmitted, usually via wires, to a central relay station at which security personnel continuously watch video screens displaying the video signals.
In some instances, where continuous surveillance is required, a single video screen is provided for each video camera located throughout the predetermined area of interest. In other situations, where the predetermined area may be exceedingly large or the number of security personnel available to monitor the screens is limited, the number of video display screens is fewer than the number of video cameras. In such case, multiplexing means is provided for switching, on a rotating basis, connections between single video monitors and the plurality of video cameras spread throughout the predetermined area.
Use of the video camera approach is effective to a point, but is notably deficient at night and at any time respecting interior security. Specifically, it is often economically impossible to place a video camera at positions whereby every locale within every building in the predetermined area can be monitored on a continuous basis.
As yet another disadvantage of the video camera approach, whether used indoors or out of doors, such systems are silent and passive. The persons whose safety is being protected are not active participants in the security monitoring system; the individuals do not actuate devices to emit alarms and thereby signal their distressed state. The passive nature of the system does not provide the protected individuals with a secure feeling such as experienced when the individual is an active participant in maintaining his or her safety and carries a device which, when activated, triggers an alarm which is audible to and/or visible by the person being protected.